Chytridiomycosis, caused by the parasitic fungus Batrachochytrium dendrobatidis (Bd), was identified only in 1998.

It affects frogs and their amphibian relatives - salamanders, and the worm-like caecilians - and has caused a number of species extinctions.

"I'm not convinced that the effect we've discovered could be considered responsible for declines or extinctions in the ways way that the spread of Bd can be considered responsible," said Thomas Raffel, lead scientist on the new research.

"It might be, however, that climate change has sped up the decline or extinction after the parasite arrived," the Oakland University researcher told BBC News.

Variable success

Over the years, various teams of scientists have conducted a whole raft of experiments to find, for example, whether Bd is more active in warm or cold temperatures.